Mayor Anthony A. Williams vetoed D.C. Council legislation yesterday that would keep the school board in charge of the public school system.

In a letter to the council explaining his veto, Williams (D) decried the school board's record, saying its oversight "includes a history of fiscal mismanagement, micromanagement of the superintendent's operational authority, and a lack of urgency regarding educational reform."

Williams, who has unsuccessfully pressed the council to give him direct control of the school system and have the superintendent report to him instead of the school board, will continue to push for that approach, said his spokesman, Tony Bullock.

"We won't get the reform that is so clearly needed in our school system if we keep the same structure in place," Bullock said. "We're hopeful the veto will give council members a chance to take a leadership role in changing the governance structure."

Some council members who supported the legislation plan to try to override the mayor's veto, a move that would require the support of two-thirds of the council members who are present and voting. The council has 30 days to override a veto of the school legislation, which it approved last week in a 7 to 6 vote.

Council member Phil Mendelson (D-At Large) said he was hopeful there would be enough votes to override the veto. He said the mayor's rejection of the council legislation further complicates the search for a new school superintendent and will lead to instability.

"In a word, I think it's destructive," Mendelson said of the veto. "It prolongs the controversy and it hinders our ability to attract a superintendent."

Council member Jack Evans (D-Ward 2) said he was pleased with the mayor's veto and hoped that it clears the way for a change in school oversight. "What's destructive to the hunt for a superintendent is the way our whole dysfunctional system doesn't work," Evans said.

School board President Peggy Cooper Cafritz did not return phone calls for comment yesterday.

The mayor proposed taking control of the school system in September, and the council voted down his plan in April. Williams said giving him control of schools would lead to a more clear line of accountability and more rapid reform. His opponents have criticized the way Williams has run other government agencies, saying he would not do better running schools.

Instead, the council approved legislation that would keep in place through 2006 the current structure, in which the board -- five elected members and four appointed by the mayor -- hires the superintendent and oversees the 64,200-student system. After 2006, the board would become an all-elected body.

Three finalists for the superintendent's job, which was vacated when Paul L. Vance quit in November, have raised concern about the oversight debate. The mayor's top choice for superintendent, former New York City schools chief Rudolph F. Crew, said the unresolved governance issue was a major factor in his decision to take a job as head of the Miami-Dade County schools instead.

The current school board structure, which was created by voters in a referendum in 2000, expires in July. If legislation is not approved to either continue that structure or replace it, the current structure will remain in place.

However, there is no mechanism to replace the four school board members who are elected from districts as their terms expire and they leave the board, said the council's chief lawyer, Charlotte Brookins-Hudson. In December, the terms of Julie Mikuta (District 1) and Dwight Singleton (District 2) will end. Neither returned phone calls yesterday.

Bullock said the mayor recognized that the matter needed to be handled quickly. He said Williams would sit down with council members to craft a bill that would gain majority support.